Hammer tacker

A hammer tacker, including:

• a housing, including a grip portion and a body portion;
• a magazine, including a rail, at least partially received in the housing, being movable relative to the housing between a stapling position and a staple-installing position, including an outlet disposed at a front end of the body portion;
• a biasing mechanism, including a push member movably mounted to the rail and a constant force spring which is rollable, the constant force spring being positionally attached to the rail through a connection portion and located at a front end of the magazine, the constant force spring being attached to an inner face of the push member, and the push member being movable to be correspondingly above the connection portion and movable to be beyond the connection portion;
• a striking mechanism, mounted to the body portion and configured to strike at least one staple installed in the magazine;
• wherein the push member further includes a protruding member protruding from the inner face, and the constant force spring is connected with the protruding member wherein the protruding member includes a neck portion and a flange extending laterally from the neck portion, the flange transitionally extends on a plane parallel to the inner face, and the constant force spring includes a hooking hole disposed around the neck portion wherein the protruding member further includes a leg portion extending from the flange in a direction away from the inner face.